The treatment of chronic viral hepatitis with interferon is effective in only about 20% of such patients. Ribavirin can also lower abnormal liver tests in chronic hepatitis C. It is hoped that the combination of interferon and ribavirin therapy will improve the therapeutic potential of the individual drugs. This study will compare the elimination of a single dose of ribavirin in controls and patients with liver disease of varying severity thus permitting an assessment of the correct dose of ribavirin and of the drug combination in patients with chronic hepatitis C.